Poor outcomes in methamphetamine-associated cardiomyopathy-a growing health issue in New Zealand.

BACKGROUND: Methamphetamine-associated cardiomyopathy (MAC) is increasingly recognised as a serious consequence of chronic metamphetamine use. Evidence to guide management and prognostication of patients with MAC compared to other cardiomyopathies remain limited. METHODS: Clinical characteristics, in-hospital and post-discharge outcomes were collected in consecutive MAC patients at Middlemore Hospital from 2006-2018, and compared with a 1:1 age-range matched cohort with non-ischaemic cardiomyopathy (NCM). RESULTS: Sixty-two patients (eight females, median age 41 years) with MAC were included. MAC patients were younger than the NCM cohort, and the majority were of indigenous Maori ethnicity. MAC patients had higher peak N-terminal pro B-type natriuretic peptide (NT-proBNP) and lower left ventricular (LV) ejection fraction at presentation. No patients died during index admission. However, there were more MAC patients (10 versus two, P=0.030) with cardiogenic shock at presentation. There were 15 deaths in the MAC patients and seven deaths in the NCM patients during follow-up. MAC patients were at increased mortality risk (HR 2.7, 95% confidence interval 1.1-6.2, P=0.029), and had a trend to more heart failure re-admissions. (HR 1.6, 95% CI 1.0-2.8, P=0.075) compared to NCM patients. Baseline LV end diastolic diameter and failure of improvement in right ventricular systolic function during follow-up were independent predictors of mortality, while failure of improvement in LV ejection fraction predicted heart failure readmission in MAC patients. CONCLUSIONS: MAC patients were more likely to be younger, male, of Maori ethnicity and have a worse prognosis when compared to patients with other non-ischaemic cardiomyopathies.

The effect of a whole heart motion-correction algorithm on CT image quality and measurement reproducibility in Pre-TAVR aortic annulus evaluation.

BACKGROUND: Motion correction (MC) algorithms have been shown to improve image quality, interpretability and diagnostic accuracy in coronary CT angiography. We sought to determine whether MC extended to the whole heart would demonstrate improved image quality and reproducibility of aortic annular measurements in pre-TAVR CT. MATERIALS AND METHODS: Twenty-two consecutive contrast enhanced CT data sets acquired for pre TAVR evaluation using retrospective ECG synchronization during a single heart beat were retrospectively identified. Image data sets were obtained from raw data acquired at 35% and 75% of the R-R interval using both standard (STD) and motion corrected (MC) reconstruction algorithms. Four data sets (2 STD, 2 MC) per patient were analyzed by 2 independent, blinded readers for aortic annular area, short and long axis, perimeter and average diameter. Image quality was graded using a 5 point Likert score (1 and 2 non diagnostic, 5 excellent). Statistical analysis was performed using Wilcoxon matched paired tests, Bland-Altman (B-A) plots and Lin's concordance coefficient comparing 35% STD to 35% MC, and 75% STD to 75% MC. RESULTS: Eighty-eight datasets were analyzed (44 STD, 44 MC). At 35%, there was a significant improvement in image quality for MC (Likert score 3.3 ± 0.9 STD vs. 3.9 ± 0.7 MC, p < 0.007). While B-A analysis demonstrated narrower interobserver agreement for aortic annular area (bias 0.03 vs 0.02 cm(2), range -0.32 to 0.39 cm(2) vs -0.50 to 0.55 cm(2)), and perimeter (bias 0.3 vs 0.3 mm, range -3.1 to 3.8 mm vs -4.6 to 5.3 mm), this was not statistically significant by concordance correlation coefficient. At 75%, there was no significant difference in image quality (Likert score 3.3 ± 0.9 vs. 3.5 ± 0.76, p = 0.454) or annular measurement agreement intervals. CONCLUSION: Motion correction algorithms may yield significant improvements of image quality in systolic CT data sets of the heart. Further validation studies are required to determine the effect on annular measurements and translation into clinical practice.

Clinical Characteristics and Outcomes of Patients with Amphetamine-Associated Cardiomyopathy in South Auckland, New Zealand.

BACKGROUND: Amphetamine-associated cardiomyopathy (AAC) is becoming an increasingly recognised entity. The characteristics and outcomes of these patients are poorly understood. METHODS: Thirty patients admitted with heart failure and echocardiographic evidence of cardiomyopathy between 2005 and 2014 and who had a documented history of amphetamine abuse that was considered an important factor in the causation of their cardiomyopathy were retrospectively identified. RESULTS: Mean age at presentation was 40±10 years with a male predominance (n=25, 83%). The majority were of indigenous Maori ethnicity. At presentation, four patients were in cardiogenic shock. Five patients required intensive care unit (ICU) admission for inotropic support and mechanical ventilation. Fifteen had severe left ventricular (LV) dilation (mean LV end-diastolic dimension 6.8±1.0cm) and all patients had severe LV dysfunction (mean LV ejection fraction 22±8%). Despite optimal heart failure therapy, LV size remained significantly dilated with minimal improvement in LV function. During median follow-up of 18 months, five patients died from end-stage heart failure and 17 had at least one readmission with decompensated heart failure. CONCLUSION: Amphetamine-associated cardiomyopathy was seen predominantly in young indigenous Maori men. They presented with severe cardiomyopathy, often requiring ICU admission. Severe LV dilation and significant LV dysfunction persisted despite treatment and mortality was high.

Management and Long-Term Outcome of Acute Coronary Syndrome Patients Presenting with Heart Failure in a Contemporary New Zealand Cohort (ANZACS-QI 4).

BACKGROUND: Acute heart failure (HF) associated with an acute coronary syndrome (ACS) predicts adverse outcome. There have been important recent improvements in ACS management. Our aim was to describe the management and outcomes in those with and without HF in a contemporary ACS cohort. METHODS: Consecutive patients presenting with ACS between 2007 and 2011 were enrolled in the All New Zealand Acute Coronary Syndrome Quality Improvement (ANZACS-QI) registry. Outcomes and medication dispensing were obtained using anonymised linkage to national data sets. A summary pharmacotherapy measure of "quadruple therapy" was defined as dispensing of at least one agent from each of the four evidence-based classes - anti-platelet, statin, angiotensin converting enzyme inhibitor/angiotensin receptor blocker and beta blocker. RESULTS: Of 3743 ACS patients 14% had acute HF. Acute heart failure patients were older (69.2±12.6 vs 62.3±12.8 years, p<0.001), less likely to have coronary angiography (66% vs 86%, p<0.001) and revascularisation (46% vs 62%, p<0.001). Immediate post-discharge quadruple therapy was higher for those with than without HF (61% vs 55%, p=0.02) but fell to similar levels by one-year (45% vs 53%, p=0.55). At four years follow-up nearly half of those presenting with ACS and HF had died. After adjustment, HF remained a strong predictor of death within 28 days (OR 2.9, 95%CI 1.5 - 5.5) and beyond 28 days (HR 1.8, 95%CI 1.5 - 2.3). CONCLUSION: Acute heart failure complicating ACS is associated with heightened risk of short-term and long-term mortality. One in three ACS patients with HF did not have coronary angiography and less than half received quadruple therapy a year after presentation.